Merge pull request #382 from sharelatex/sk-spellcheck-underline-retina

Sk spellcheck underline retina

services/web/public/stylesheets/app/editor.less

@@ -138,6 +138,10 @@
 	.spelling-highlight {
 		position: absolute;
 		background-image: url(/img/spellcheck-underline.png);
+		@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
+			background-image: url(/img/spellcheck-underline@2x.png);
+			background-size: 5px 4px;
+		}
 		background-repeat: repeat-x;
 		background-position: bottom left;
 	}